Worldwide, there are an estimated 750 million people who use English as a second language, as compared to 375 million native English speakers. In addition, in United States alone, there are an estimated 4 to 5 million students with limited English proficiency in public schools, as well as a large number of international students in American colleges and universities. These numbers highlight a growing need for support for non-native speakers of English who must perform academically in English, though their English language proficiency is limited.
There are several different types of errors that non-native speakers make, some of which are usage errors. One such error is a collocation error. A collocations is a collection of words where the words of the collection occur close, although not necessarily adjacent, to one another, where the collection of words is arbitrary but has a conventional meaning, and where the collection of words occurs more frequently than by chance (e.g., “strong tea,” “hold an election”).
Various studies have found that knowledge of collocations is an important part of language learning. In tests of collocation abilities, native speakers usually outperform non-native speakers significantly. Collocational knowledge may be viewed as a source of fluency in written communication, and the quality of collocation in terms of variety and accuracy may be indicative of the quality of one's writing ability.
While the frequency of collocations in a text or speech can vary, the presence of an atypical combination of words, such as “powerful tea” instead of “strong tea,” can disrupt communication. Since collocations are not rule-governed and vary from language to language, each one needs to be learned. Considering the great number of collocations that are in common use, teaching them to English language learners is a formidable task. Knowing which subset of grammatically possible utterances is actually commonly used by native speakers is an immense problem for even the most proficient of nonnative speakers. Dictionaries and thesauri, common aids for an English learner, are often of limited value when one does not know the appropriate collocation and must sort through a list of synonyms to find a contextually appropriate one.